In business seasonal variation refers primarily to systematic variations in demand for products and services in a cyclical fashion at different within a recurring time period. For example, the demand for umbrellas is likely to have a yearly cycle, in which the demand will be high during rainy season and low in other seasons.

The periodicity of demand can be any repeating time period such as year, month, week or day. Generally in business cyclical or seasonal variations of time period more than a year are not considered.

The reason for seasonal variations are changes in the environment or other cultural factors cause people to have different types of requirements at different times of the seasonality time period. For example, a fast food outlet or a restaurant will have a daily cycle based on the usual meal times for people in general. Similarly a super market will also have a daily cycle based on shopping time convenient to its customers. In addition both these types of businesses will experience a weekly cycle as well as a yearly cycles. Banks are likely to face a monthly cycle as many people get paid their salaries at the end of each month, and are more likely to make withdraw money from their accounts at the beginning of each months soon after their salaries are credited.

Just as there are seasonal variations in demand there can be seasonal variations in other activities of other activities of business. It is obvious that seasonal variations in demand will result in seasonal variations in all all activities connected with fulfilling those activities, But there are many other activities with seasonal variations. For example, all utilities may bill their customers on a monthly cycle, causing a monthly seasonality in billing as well as bill collection activities. Similarly all credit card billing also follow monthly billing and settlement cycle.

Because of the variation in level of demand and activities, organization may also make changes in the processes that they follow. A typical example of seasonality in processes is by restaurants. They may put up extra tables and use part time staff to handle extra rush of peak hours.

Some other prominent example of product and services with high seasonality are listed below.

Christmas trees are mostly purchased during Christmas festival.

Ice creams and cold drinks have much higher demand during summers than in winters.

There is heavy seasonality in demand of clothing. Particularly warm clothes have much higher demand during winters.

Local transportation in metro rails and buses has a heavy daily as well as a weekly variation in number of commuters.

Demand for hotels and all other facilities in tourist location is much higher during their respective tourist seasons.

Demand Stationary used by students is much higher wen schools and collages are open than during vacations.

Demand for toys and presentation items is very high during Christmas and other festivals when people exchange gifts.

There is heavy seasonality daily in demand for utilities such as electricity, piped gas and water.

However there are some items with very low or no seasonal variability this will include items of common daily use or consumption such as bread or salt.